Evaporative odorizer for gas



Patented June 4, 194G UN TED. S A ES A NT F E "2,203,362 'EvAPoRATlvE ODORIZER FOR 7 Joseph F. Putnam, Berkeley,'Calif.,.assignorto Standard Oil Company of California, San Francisco, Oaliii, a corporation oi Delaware Application .August'ZO, 1938, Serial No. 225,950

' comm; (o1; 261--65) This invention. relates to devices for introduc ing a volatile .liquid material having a distinctive odor into a confined flowing "stream of gas, and particularly refers to an apparatus for accurately 5 controlling the rate of evaporation of a volatile odorant material and introducing the gas thus formed into'a natural gas line at a rate substantially proportional to the rate of gas. flow in said line and further controlled. bythe variations in density of the odorant material, Those evaporative types of odorizers that have been used for this purpose are subject to atmos pheric temperature variations, that change the rate of evaporation of the liquid andchence-the odorizing rate. Itis well known that .asa liquid odorant, particularly one which is not-of a constant or nearly constant boiling mixture, is permitted to evaporate freely its density and also its rate of evaporation will change. Other factors, such as temperature variations, also have a detrimental effect upon the constancy of the rate of evaporation.

This invention comprehends broadly an im- I proved evaporative type odorizer in whichmeans are provided for varying the rate of gas flow through the odorizer in accordance with variations in the density of the liquid odorant which is being evaporated. This action includes a modification of the rate at which gas may be by-passed 30 from a gas main by means of an orifice therein, to pass through the evaporating chamber and there be partially or entirely saturated with the vaporized odorant liquid.

It is an object of this invention to provide an .3 evaporative type odorizer which will contain a minimum of moving parts and an entire absence of small passages, orifices, and the like.

A further object isto provide an evaporative odorizer in which variations in density of odorant 4U liquid, for example, those caused by introducing a fresh charge of odorant liquid, temperature variations. and the like will be corrected by selfcontained means so that a substantially constant odorizing rate will be maintained.

Another object is to provide an evaporative odorizer which will operate on very low pressure differentials and with a minimum of attention and maintenance. 0 These and other objects and advantages will be more. fully apparent from the following description and from the drawing which forms a part of this specification and illustrates a preferred embodiment of the invention.

The drawing is a diagrammatic vertical sectional view of an odorizer of this type applied to -a.:natural=gas line. Y r 2 Referring. to the drawing, the reference nu- .meral iii-designates a gas line through which naturalor. other. normal-1y .non-odorous :gas is passing in the directionindicated by the arrows. A pressure dilierential producingmeans suchas an orifice lor gate valve L! is positioned; in the line All andgserves to divert ,a, portion ofthe gas through high-pressure conduit 12, into chamber M and back intoline Hi through low-pressure conduit 13. This gas, being .more or less satu a valve I5 to maintain a constant liquid level in chamber M.- If desired, float l8 could equally well be mountedin chamber M or some other means provided for holding a constant level in that chamber. the vapor space in chamber 14 and that in tank 15, a pressure equalizing conduit 28 connects these two spaces. Tank I5 is preferably provided with a filling nozzle 2| and a gage glass 22. A similar gage glass 23 may be provided for evaporating chamber M to indicate whether or not the constant level means are functioning.

If the rate of evaporation of the odorant liquid is such that an extended wetted surface is desirable in chamber l4, this may be provided by a plurality of battles it, which may be of some capillary material such as cotton, woven asbestos, or the like.

In order to control the rate of gas flow through the vapor space of chamber 14, there is provided in conduit 13 a valve seat 25 in which is mounted a valve member 26 attached by means of a stem 2'1 to a float 28, the latter being guided by vertical members 29 to assume a positionin the odorant liquid in chamber 14 according to the density of that liquid. By the construction just described an increase in density of the liquid which is normally accompanied by adecrease in its evaporation rate will cause float 28 to rise and open valve 26, thus permitting the pressure differential across orifice H to pass a greater quantity of gas through the vapor space of chamber I4. Conversely, if the density of the liquid should decrease as by an increase in temperature or by the To equalize the pressure between introduction of a fresh charge of odorant into tank I5, float 28 will sink in the liquid in chamber l4 and reduce the rate of gas flow through that chamber. In this example the valve is indicated as being within conduit [3 but it is obvious that it could equally well be positioned in conduit l2 or within chamber l4. valves for conduits I2, l3, l6 and 20 could be provided and will ordinarily be installed for convenience of operation and maintenance. As they form no part of this invention, they have not been illustrated or described.

Although a specific arrangement and construc-- therein without departing from the invention,

and all such modifications "as come within the scope of the appended claims are embraced,

thereby.

I claim:

1. An evaporative odorizer comprising a closed chamber adapted to contain a liquid odorant, conduit means for passing a stream of gas into and through said chamber, and means including a valve means above the level of said liquid odorant responsive to the density of said odorant liquid for controlling the-flow of gas through said conduit means said density-responsive means being located without the path of gas passing through said chamber.

2. An evaporative type odorizer comprising an evaporating chamber, a'liquid odorant inlet for said chamber, means for maintaining a constant odorant liquid level in said chamber, means for passinga stream of gas into and through said chamber, and means including a valve means above the level of said liquid odorant responsive Also, control position of said float.

5. An evaporative type odorizer according to claim 2 in which said last named means comprise a float in said liquid and a valve responsive to said float, said float and valve arranged to decrease the gas flow rate through said chamber with a decrease in density of said liquid odorant.

6. An evaporative type odorizer comprising an evaporating chamber, an odorant storage tank,

an outlet conduit connecting said tank to said chamber, a float valve for maintaining a constant liquid level in said chamber, a pressure equalizing conduit connecting thevapor spaces of said chamber and said tank, a gas inlet conduit for said chamber, a gas outlet conduit for said chamber at a point above the liquid level therein, said conduits adapted to be connected to a source of differential pressure, a valve for one of said gas conduits, and means in said chamber respon-.

sive to the density of the odorant liquid therein for controlling said valve, so constructed and arranged that the flow rate of gas passing through said chamber will be a function of the pressure differential impressed upon, said conduits, and a function of the density ofsaid odorant.

JOSEPH F. PUTNAM. 

